(a) Field of the Invention
The present invention relates to a fusion peptide wherein a self cell-penetrating Tat peptide (transactivator of transcription peptide) is bound to a human parathyroid hormone-derived peptide, and a skin slimming cosmetic composition comprising the same.
(b) Description of the Related Art
Human parathyroid hormone (hPTH), which is a peptide hormone consisting of 84 amino acids produced in the parathyroid of a human body, functions for controlling homeostasis of calcium in the kidneys and bones, and administration of a small amount thereof influences metabolism or bone formation [Morel F., et. al., Academic press, 1983 39, 271; Norman, A. W. et. al., Endocrinal Rev., 1982 3, 336]. In addition, parathyroid hormone functions for calcium control, blood vessel contraction, lymph flow, adrenalin control, etc., and promotes lipolysis. Particularly, it has been reported that a peptide consisting of amino acids 1 to 34 of the amino acid sequence of parathyroid hormone acts on human adipocytes to promote lipolysis [Werner S. et. al., Horm. Metab. Res., 1973 5, 292, Tanigushi A., et. al., J. Lip. Res., 1987 28, 490]. It was expected that a parathyroid hormone-derived peptide is effective for slimming from the report that if a parathyroid hormone acts on an adipocyte recipient, lipolysis will be promoted by a control mechanism of promoting cAMP production. Therefore, as a result of synthesizing various peptides and screening, it has been clarified that peptides of amino sequences 9 to 19, 12 to 16, and 12 to 14 of parathyroid hormone are effective for slimming (France Patent Application No. 2788058, PCT Laid-open Publication No. WO 00/40611, Richard L., et. al., S.P.C. 2001, Dec. 30). However, these peptides have weak skin absorbency due to water-solubility and thus it is largely difficult to anticipate lipolysis effects. Therefore, there is an urgent need for development of a novel skin slimming agent having increased absorbency through skin and thus maximizing slimming effects in a living body.
As one method for increasing skin absorbency of these peptide slimming agents, a method of grafting a long chain fatty acid such as palmitic acid on a peptide has been suggested in order to increase fat solubility of the peptide (France Patent Application No. 2788058, PCT Laid-open Publication No. WO 00/40611), but the absorbency increase was not largely improved.
Accordingly, there is a need for development of a novel skin slimming agent that does not cause irritation on skin and that has increased absorbency through skin, improved stability, and maximized slimming effects in living bodies.